Mechanical musical instrument.



mselgaso HP'ATENTED JUNE 23, 1908.

I e. B. KELLY.

MEGEA GAL MUSICAL INSTRUMENT.

APPLICATION EJEL ED JUNE -25, 1906 3 SHEETSSHEBT 1.

VVENTOR.

v ATTORNEY,

No, 891,556. PATENTED JUNE 233M993 G R. KELLY.

MECHANICAL MUSICAL INSTRUMENT.

3 SHEETS-SHEET 'Z l VITNESSES: y JNVE/VTOR. i r BY L 'Q%;E$/1 I rampearin the specification.-

being onthe-plane 1-{1 of. 3. Fig. 2 is a instrument.

having two setsof ducts 12 and. 1'3.-- O

GEORGE BQ ELLY; 'oFBosToN, MASSACHUSETTS, assienoa'ro THE A oLiAn GOMPANYLYOF NEWXORK N Y A'coaPon 'rIon-or CONNECTICUT.

MECHANICAL musrcan msrnumm'r. j

a No. 891,550.-

: specificationotl etters 2a t'ent I a Patented June 2a; 190

Appficationfled June 25, 1906. 4 Serial No. s'aaese.

r5 cll -whom'it may concern:

.Be-i known that-"I, GEORGE BQKELLna citizen of the United States; and a resident of Boston, county ofiSuiiolk'; and State of Mas-- sagchu'setts; have invented certain. new and; useful. Improvements in: Mechanical Musical 1 Instruments, ofwhich the following is a specification.- i p a My invention relates to mechanical musical instrument's such: as are controlled by the passage 'of-a-music she'et over a tracker. v

Itparticularly' refers to instruments providedwithJa-double tracker board, that" is, a tracker board havingatwo independent sets ofi'ducts thereim; Its object is to enable'such instruments; inconnection' with a perforated music sheet jadagged thereto to lplay anyder sired1seti-of ree' .er sounding evlces, from A further-object of the-invention is to ena able the operator by means of manual stops to controlfthis pla inggof the sets 'ofunote sounding deviceso various characters'iso as" toplay' some'frornione andothers' 'f rom the other .setof ducts at will; V v Further objects of theinvention 'will -ap- The drawings show the device as applied 'to a 'r'eediorgan mechanism actuated by superatinosp'heric pressure.

In the drawings, Figure 1, is a transverse-c vertical sectionof so much of a. mechanical musical instrument asis'necessary to illus-,' trate myinvention, aportion of the drawing partial transverse vertical section of the instrument, part of which is taken through the plane 22 of Fig. 3. Fig. 3 is a longitudinal verticalsection of a portion of the instrument through the lane 3.3 of-Fig. 1. longitudinal orizontal section of a portion of theins'trument through the plane 4'-4-of f Fig. 5 in vertical section'shows a des tai Fig. 6 is'a' partial front elevation of the In, the drawings, 10 designatesa pressur chamber, into which, extends a trackerthe: tracker 11 is moved the perforated 7 sheet- 14 mounted on a music roll 15 and adapted to wind 'ona take-upro'll 16. As

from a cham vention it is-not' necessary that t ey'betfuf ther illustrated or described, 'llhaveshown thetwo sets of'd'ucts 12 and 13 in the piesent staggered relation, in the tracken boa-rd: 11',

but It is obvious that they may be arranged".

in a single line alternating with each-other; if

desired; in'which case the Width of=the-musicf roll- 14 would. necessarily be slightlyin:

creased. Leading from each 0f the ducts 1 2 is-aflexible tube 17 connecting to a. assag e' 18, at the end of which is mounte a; di'ae phragm '19- of a double valve 20. The; 1 asl'iiown andform no part ofthe page 18. is provided with a suitable .b eed" .f'

'e21. I The double valve-'20 is adapted to-alter nately admit to the connection: '22 atmosheric air or airunderpressurefrom a'cham her 23'." It is of course understood that the chambers 1'0 and 2.3., as well as several'other' pressure chambers hereafter-tobedescribed, are connected to asource of 'pem'imatic pressure, not shown. :The tube 22 connects with apassage- 24', whichis-closeilibylthedia phragm 25 of a double diaphragm-valve26,

which acts to pneumatically connect the past? v sage 27 with atmospheric air or 'with'air under pressure from a chamber 28, In likev manner each of the lower set of ducts"'13-;jis"

connected bya tube 29 to a as's'a 'e 30'having a bleed hole 31-andclosed y a diaphragm passes atmospheric airor air under-J pressure passage 0.

,32 connected with a double valve 33, which er 34zto a tube 35, which-in. turn connects with; a-passage -36'uI ide1t; a 'diaphra'm' 37" operating a double-'valve,.-3,8, which a ternatively admits atmospheric; air,- or air under pressure from a chamben391toa pr ss isp'e'rmitted to pass through -a tu be 45 I th function of whichiwillhereafterap. ear.

'reed: 4 8 I a means of moving the music -sheet-,ai-e-well. p

t eggpa'ssage 30- beforev described; 1 51 he 7 pa fag-"e 30 provided with a ilapfwalvei ifi," 10 0 but it is obvious that there may be any-de- 1 sired number in the instrument, as indicated "with an operatin pneumatic 52 I alrea y described. The passage 54 is opene or closed to the ports57 and 58 by means'of in Fig. 6. Each reed cell 47 is connected by a passage 49 closed by a valve 50 to a presformed in a board 56 which constitutes a 15 horizontal partition extending longitudinally of the instrument. The diaphragm 59 and 60have'at'each side of the passage-54 a ort marked 57 and 58 respectively, one lea ing upward and the other downward to the respective faces of the board 56. Each port' 57 connects with one of the assages 27 and,

each ort 58 with one of t e passages 40,.

diaphragms 59 and 60 respectively secured to the upper and lower sides of the board 56.

I Above the board 56 are two, windchests or chambers 61 and 62 respectively, separated b a vertical partition 63 placed so as to di-' v de the treble from the bass end of the instrument. In like manner below the board 56 are wind chests or harnbers 64 and65 separated by a partition 66.' y

Arranged, in the present-instance, above the manualv keys 41 of the'inst'rument. are

. stop manuals, preferably superposed in palrs, one pair of these stops being indicated at67,

. '68 respectively, (see Figs. 1 and 2 of the drawings). It is of course understood that there is a pair of these manuals at thetreble end of the instrument and a similar pair at the bass end for eachstop or set of reeds, as harp, oboe, flute, trumpet, etc., (see Fig. 6). -.Each of the stops is provided at its rear end with a finger 69 adapted to rock block valves7 0,. 71 respectively, mounted on pivots 7 2. Thesevalves are alike and inTFig. 1

the section-is distorted slightly to show the valve 71 controlled by stops 68, omitting the that is accurately shown in 1g.

valve 70 controlled by the sto 67 because i 2. .The

valve 70 controlled by the manual stop 67 acts toadmitair to a port 73, which is connected by a tube 74 to a recess 75 in a valve box 76,, (see Figs. 2' and 3). The recess 75 is closed by-a diaphragm 77connected to a double dia hragm valve 78 operative to alternativ'ely a mit atmospheric airor air under ressur from the chamber. 51' through a passage 79 to the chamber 61, it being understood that-the box 76 communicates-with the chamber 51 through a port 80. In like manner the manual sto 68 operates to rock the valve 71 and there admit air to a port 81,

83 in a valve box 84, the recesss SB-being closed by the diaphragm 85 connected to a double'diaphragm valve 86operative to ad-' mit airfrom the chamber 51 through passages 87 and 88 to the chamber 64.

my device herein illustrated, the draw stops duplicated at the other end of the instruings, so that one pair of-stops 67, 68 is conalso understoodthatthe numbers of pairs of these steps; at each end of the instrument .c'orresponds with the numberof reed-chests 51, several of the stops being shown in Fig. 6 of the drawings. l-will first d cribe the operation of the device as efiected by the movement of the perforated music roll 14 overthe tracker ducts d ,12-and 13. It is of course understood that the music roll perforated for an instrument of this particulartype, so-that, e.'g., the solo portion of thecomposition is adapted to pass over-the tracker ducts 12,- while the-accompaniment A portion'thereof passes over and registers with the 2tracker' ducts 13. It is evident that when a perforation in the music sheet. passes over oneof the ducts 12 pneu-. maticressure from the chamber 10 will be to lift the-diaphragm .19, by which the valve I osed"to atmospheric air and o enedi to .the pressure chamber 23,' from .w 'ch neumatic pressure .will'pass through the tu e22 and passage 24 to raise the diaphragm -25, by which the double valve 26 is closed to the pressure-chamber 28 and opened tolatmosphere. This permits the exhaustion of pressure from the passages27 and 57,"the latter being in the, valve 55. As, .however, air pressureexists in allthe cham here 61, 62, 64 and 65, it is evident that all the diaphragms 59 and 60 will beheld close toftheir seatsso that no communication is. possible between the passag 57 and the passage54." If,however,one of the draw stops 67 located at the treble end of the 'instrument had previously been drawn out, (see Figs. 2 and 3) the pressure in the corresponding chamber 61 would have been exhausted by reason of the movement of the valve 78' caused by exhaustion of pressure on the upper side of the, diaphragm '77 thro h the passage 75, tube 74. and port 73. n this case the pneumatic pressure in the tube 57 would suffice to raise the diaphragm-59, thereby opening communication between the passage 57 and the-passage 54, which leadstow the particularpneumatic 53 connected with the particular tracker ductuncovered; Air being exhausted from the pneumatic 52 which is'connected y'a tube 82 to a recess the pressure in the chambe 51 acts to collapse t will be understood that, in the form of nected with the'treble endofthe instrument and the other with the bass end. It will be ormanual stops 67 and 68 and all the parts i above "described as connected therewith are i ment,-las clearly shown in Fig. 3 'of the drawexerte through the tube 17 and passage 18' the pneumaticv and to'openj'the .valve 50, whereby, in the present instance, the reed'48 is caused, to speak. It is obvious that by opening the appropriate treble manual stop -67,, anytreble setor stop of reeds may. be

made: ready for actuation by perforations in thetracker duchnas described. It is,obvious.,

that in the-same way a; perforation in the sheet 1.4 ,pafssmgyover one offthe ducts 13' of the lower series will act'through the tube 29 and passage 30 to raise the valve 33, which in; turnc-acts to'raise' the valve 38, thereby er mitting exhaustion of air from the passage l0 which connects wi th the )assage 58;in,rthe'.valve tracker ducts 12 be closed, which may 55. To cause anoteo the treble set of any particular stop. of reeds to be' -thus sounded, to draw out .the ap ropriate'. .68, which permits t e inov'ementg-of such of the-lower diaphragms 460 in] the ,wind-chest (S las are pressed downwardly it is necessary lowenmanua by thepneumatic force admitted thereto through the-particular passage 4.0 connected, as already described, with the particular duct, 13 in the tracken It is obvious that the bass end of the: scale in each of the. sets or stopsof reeds is similarly operated by the corresponding stop manuals at the leftof the, instrument. It will-be noted that all these stop manuals are conveniently located above the keyboard of. theinstrument so as'to be easily manipulatedbythe operator., i In the present instance]: have'shown asingle set of manual keys 41 for playingthe instrument.

' When the instrument, as herein shown, is to be manually played, it. is necessarythat the be done by leaving an' imperforate portion of the music. sheet thereo'ver, or inany other we:

known ordesiredkmannerl. The depression of any key 4 1 will act through the lever 42 to raise the lever 43 and admit pneumatic pres-. sure from the chamber 44 through the tube 45 to the assa'ge 30. The efiect of .this pres .sure will e to close the flap valve 46 and at the same time to raise the diaphragm32,

thereby moving the valve 33., the effect being precisely as already explained connection.

with the movement of a perforationin the.

:music sheet over the duct 13:.correspondingi to the key manually depressed. It Willthus be seen that the instrument ma he operated manually-insteadfof bythe per orated music sheet, if desired.

- It is obvious that many mechanical changes may be made in my device without departing from my invention. 1 e A I What-I ola'im-isr.; 1 .w 1. Musical apparatus having a plurality'of sets ofAnote-sounding. devices of different characters, two sets of tracker .ducts and pneumatic connections for operating the sounding devicesfrom each'setof ducts, a.

double set of draw stops, one pair foreac'h set of note sounding-devices, and a pluralityof means, one for each stop, controlled'thererespective sets of tracker ducts.

,for cutting on ;tracker'duct.eonnections at will.

.of each set ofsaid tracker ductconnections.

- of tracker-ducts, two sets of wind ways, each of which leads from one of said sets of tracker.-

I ducts toward saidset of note sounding devices, and aplurality; of; manually controlled wind ways with the corresponding portion of said. ,set of note soundingfidevices at-wlll;

by for preveptingorf f of tliefrespeetive', sounding devices from the.

2.' 'In' a mechanical musical instrurnent, a 7

-p1urality ot-sets oftracker ducts; a set onfio stop of note soun'ding. devices, an in dependent connection f rojma-tracker duct of each l set to the respective lncte sounding-device,- and a plurality f inually controlle'dmeans. 4

ions. of each jset o f ,s' 'dtracker duct'connections atiw ill. 3.. In a mechanical :music'al- "nstrument,

plurality-of "setsj ofhtracker, ducts, alfset or stop of'note sounding devices, anindefp end j, v

.eac rso ,Set to the respective note sounding device, I anda plurality of. manually controlled means xincluding apair of stop manuals located cone,

y'eniently' to the hand of. the operator for cutting" out-aportions-"of each :setofsaid 5. In a mechanical musical instrument,- a fl plurality of sets-of'tracker: ducts, a SGt'OP stop of note soundingdevices, an independent connection from atracker duct of eachset.

to the respective note soundin device, anda ,10'0 plurality of manually control ed means ine nding, a pair ofstop manuals located e01i-'.

eniently to the hand of the o erator for;

cutting out either the bass or tre le portion,

atwill. I 6. Ina mechanical musical instrume nt,-a set or stop of notesounding devices, two sets ducts toward s aidset of note. sounding deep vices, and a plurality of manually controlled means forjseparately' connecting either of a plurality of portions Jot. either of said setsof wind ways with the corresponding po'rtio'n of said s'et of note sounding devices at will.

,7, In a mechanicalmusical instrument, a

- set or stop of note soundingvdevices twosets of tracker ducts, two sets-otwind ways, each ggl,

.of which leadsffrom one of said sets of tracker, 20

means .for, separately. connecting either .the. b'asspr. treble 'portion of each ofsaidvsets of.

' 8-. ln'a mechanical musical instrument, a plurality .of sets of tracker ducts, a. set or StQPyQflIlOtG sounding-devices, an independ-.' entconnection from each tracker/duct of'130 eachset to the respective note sounding deu vice, said connection including a diaphragm zvalve, .a" assage to said valve and a single assage' rom said valve'to the note sounding device, '"and manually controlled means for actuating said diaphragm valves respectively to connect each. of said firstnamed passages With said last-named passage, for the purposes specified.v

9..,In a'mechanical. musical instrument, a

fplurality of sets of tracker. ducts, a set .or

- stop of notesounding devices, an independ-. '-ent connection from eachtracker ductof.

the diaphragm valves respectively; of the" each set to the respective note sounding .device, said connection including a diaphragm valve, a passage to said valve-and a single passagefrom said valve to the note sounding device, two pneumatic. pressure chestsyfor respective independent connections. and independent manually cnntrolled means for exhausting pressure from each-of said chests, for the purposes specified.

10. In a mechanical musical instrument, a

plurality-ofsets of--.tracker ducts, a set-or stop of note sounding'devices, an independent connection frompeachtracker duct-of each setto thelre'spective note sounding device, said connection including a diaphragm valve, a passage to said-valveand .a single passage from said valve to the note sounding device, two pneumatic pressure chests for the diaphragm valves. respectively of'the" res ecti've independent connections, and in ependent manually controlled means for exhausting (pressure from each of said chests,

each of sai manually c0ntrolled' means including a sto valve actuated specified.

11. In a mechanical musical instrument, a plurality of sets of tracker ducts, a set or stop of note soundingdevices, an independthereby, for the purposes ent-connection from each tracker duct of each setto the respective note sounding device, said connect-ion including a diaphragm valve, a passage to said valve and a single passage from said valve to the note sounding device, two pressure chests for the diaphragm valves respectively of the. respective independent connections at the bass end of lhe instrument, two pressure chests for similarly controlling the valve diaphragmsat the treble end of theinstruinent, and independent manuallycontrolled means for exhausting pressure from the respective chest-s, for the purposes specified. Y

12. In a mechanical musical instrument, a

plurality of sets of tracker ducts, a set, or

stop of note soundin devices an independent connection from eachtracker duct 0t each set to the respective note sounding devices, said connection including a diaphragm valve, a passageto said valve and a single passage from said valve to the note sounding manual and a pneumatic.

d vice, two pressure chests for the 4 diaphragm valves respectively 'of the respective independent connections at the bass end of' the instrument, two pressure chests -for.

similarly controlling the valve diaphragnis at thetr'eble end of the instrument, and inde endent manually controlled means for exstop manual and a pneumatic valve actuated thereb for the purposes specified. 13. amechanical musical instrument, a

plurality otsets oftracker ducts, a'plurality of. sets or stops of note sounding devices, an independent connection from each tracker duct of each set leading to the sounding de vices. for the corresponding note ineach of said'stops, and .a plurality of manually controlled means for-permitting and preventing the actuation of any stop of said note sounding devices from the respective sets of saidtracke vill, the purposes specified'.-

w 1 1. In a mechanical musical instrument plurality of sets of tracker ducts, a plurah-t-y' of sets or-stops' of note soundingvdevices'an independent connection from &Ch tracker duct of each set-leading to the sounding (le-r "vices for the corresponding note in each of said stops,'and a plurality of nianua-llycom trolled m'eansfor permitting and preventing the actuationof an stop of said note sounding devices, from t e respective sets'of said tracker ducts at will, each ot'said manually controlled means including a air of stop manuals and a val e controlled by each of them.

1 5. In a mechanical musical instrument, two tracker ducts, a note sounding device and a connection between said ducts and said note sounding device, including'a valve board having 'a. transverse discharge passage connected to said note sounding device and austing pressure-iromsaid chests, each of SS/1d manually controlled means including a opening on the opposite faces of said board, I

and two passages each' connected to one of said tracker ducts and extending respectively t0 the opposite faces of said board, and

a diaphragm on eachface of said board, each of said diaphragins covering one end otsaid first-na1ned passage and the endof one of.

said second-named passages, for the purposes speclified.

16. In a mechanical musical instrument. two tracker ducts, a note sounding device and a-connection between said ducts and said note sounding device, including a valve I board having :1. transverse discharge-passage nections therefrom for actuating the respec 'tive' devices, manually control-led means forrendering either set of connections inopera-h' tive or operative at will'ano'ther set'or stop of note sounding devices of"difierent' character" and ,'c,onne'ctionsfromv the S3i d tWO S6tS of: tracker ducts for actuatingthe respectis en devices thereof, and manuall controlled" -means for rendering eacltset of ast said conin combination; two "or more sets of sounding means for rendering operable-or inoperable of said board, and independentmeans forale: ternatively admitting. pressure to" and ex specified.

' matically controlled valves controllingjcham either set without affecting either the other the respective devices, two independent as; I sages having connections for actuating a the sa d neumatics for said note, means for sev--.

the passages and the neumatics, and sepas 60- from either of said-tracker ducts. 1

said second-named passages,.means for con-e. necting all of said passages with asource of pneumatic pressure a wind chest on :each s de.

hausting it from each of said wind chests for' actuating said diaphragms,-for;the -'purposes" '17. Ina mechanical musicalinstrunien't, in combination, a plurality. of sets of tracker 1 ducts, a set or stop of'no'te sounding devi'cs having connections for the respective notes thereof to therespective ducts -of each-of said sets, and manually'controlled means for preaventing or permitting the operation 'of ,said note sounding devices 1 mm: the sets "oftra'cker' ducts respectively said nianually con trolled means including-two series of 'pneu'ihers forthe respective'seriesfand meansfor changing the pressure in the last said-cham--' bers. -i-

y 18. In a mechanical musical. instrument-, in combination, a set or stopof note sounding devices, two sets :oftrackenducts'and con nections inoperativeor operative at willindependently of the'first said connections...

19. 'In a mechanical-musical ins-truinent,

devices, two sets of tracker ducts and means controlled thereby for actuating anyone sounding device from a corresponding duct of each set of ducts, andman-ually'controlled the means. for actuating the sounding devices of either set thereof from thetracker ducts of a plurality of note soundingdevices for that note, a plurality of-Pneumatics controlling erally closingeach said connection between rate tracker ducts and controlling means for the respective. passages, whereby any of said note sounding-devices maybe played at-will 21. Mechanical musical apparatus having @means cpmprisin a diaphragm covering two 522. Tn combination a stiop sctflQfi trackerduct a plurality of note. soundingfde jices qiorithatg note} a "plurality of neumatics controlling, the respective devices, twoindependen-t; sages having;.connections for aptuati the said pneumati'cs' for said note, means r severally closing each. saidconnection; tween the passages and, the .pneumatic s said .pdrtsin eachsai connection and. pneumaticij';

not'je;-sounding devices of like character, gand f thepneumatrcs' for causln the respective;

each of said pneulnatics controlling. valves;

. e b i p mgm -v ;a -meansjfor permittingi orpreventing their; 1' "being sounded through? reither of. -two pne'umatic' :cdnnections fora respective; notes; 1 it pair. :ofchar'nbers, pneumatic- -;fconnections theretofasfi pt diaphragnas for athe respective pneuln'a :ei r a c-Op a a M i qdiaphragms .in':. each chamber',-.a" plurality; of, zdncts eaich -20 enin'g. against ensr the diahragmsg an "InaIIS for varying-the-pres'surefl 1n "the said chambers} to control the sets "of aph gmstherein 1.1.5 ,1: :1. f' 241 In om'b'nation ;.agrpilgumatic and its. controlling duct 54,- a chamber having a portfor theduct 54, an adjacent port cooperating therewith, and a diaphragm secured a ainst said 'ports, a duct' communicating wit the last said ports, means for varying the pressureinthelast said duct to .operate the pneumatic, and means for varying the-pressure in said chamber to permit or prevent such operation, and asimilar chamberfport", adja: cent port, diaphragm, duct, and pressure. va g means in slmilar combination with, the first said duct, whereby the saidneumatic may be operated from either 0 two independent connections atiwillq. 7 I i 25. ln'eombinatiorn'a plurality-offsets of note soundingdevices having. corresponding setsof pneumatics forcausing them-respectively to sound,- two sets of actuatingpas. sages for independently operating .the re-. 'specti've pne'umatics, and each connected to act on Pneumatics indifferent sets, and a plurality of-devices for cutting off comn1uni-- cation between-either set ofactuating'passages and the pneumatica andseparate sets 'of tracker duc'ts'and controlling connections for the two sets of actuating passa es."

in combination for each one ofseveral notes,

'70 meansflfor ,pressingthe; diaphragm against;

notes-a0 sound 'two control ing:passagesfor.i

and rconnections tor each 1 jsaid passage for "sounding t he respective notesg two 1 series-of: 'diaphragms and:cooperating:portsfproviding, I

one diaphragm for each of said .c onnect i ns respectively, and two?chamhers and gqvind connections=respectively controlling thesaid a:

liio

- 26. In combination with a plura ity'of sets 1st I fgnote-sourfdingdevices, two setsof tracli erf gluctsand connections from each set 'nectipns, fofi perrnittingor'prev'ent 10f soundi said s for permitting f amusing the respective notes'to be soundp ed one ofjsaidpair of stops b- "devices being operatedlby one 'ofthe sets 0 tracker .ducts, and the other-of =vicesbeingoperated .oftrazcker ducts. I

27. In combination,- a plurality of-sets of: note sdunding devices, a set'of tracker'ducts andrc'onnections therefrom for operating the note sounding devices, a set'of draw stops and devices governing the said connections 7 or preventing the operation of the respect vesets'of sounding devices by, setof tracker l ducts'and connections. therefrom for operatingthe'note' sounding devices; and a second; set of draw stops and devices governing the isaidtr ker ducts, a second .last said connections for permitting or pre venting and the respective sets of passages, and two sets of pneumatic means having means .for varying the said pneumatic means."-

-t e set p i airof stops having connectionsfor per-- jmitt ngor preventmgbthe setof sounding dey the other of said sets the pressure-therein and actuating 29. 1Incombination with a pneumatic, in which pressure is to be varied, a valve board having a pair of adjacent ports and a dia- .phragm covering them, another pair of adj acent ports and a diaphragm covering them,

one ofeach'pair of said ports having communication with the said pneumatic, means for:independentlyv i the pressure in ea'chiof the other "portsto thereby vary. the pressure; in the said pneumatic,- and inde-' pendent' means for varying the pressure on the two diaphra'gms independently and ,thereb controlling the said ports.

130, n combinat'lon'with a set 'of ducts, in 'hich, pressure is 'to be -va 1'ied,'a chamber having a set of pairs of'ports, to one of each air of which 7 the said "ducts respectively ead, a set ofpneumaticconnections for sev-.

erally varying the pressures in; the others of j said ports, a set of diaphragms' in said chamber 'for the respective pairs of ports, means for varying the pressure in the said chamber second such chamber, ports, diaphragms, set

of"'conn'ections,i and diaphragms similarly .connectedfto'thejfirstsaid ducts,- and indethe pressure iny the said ducts pendent means for 'varyin said second chamber, where p may be controlled independently from either of the said setsof .connections.

In testimony whereof I have signed this 7 specification in-the presence of two subscribifig witnesses I p v GEORGE B. KELLY.

Witnesses: a

1 GEO. L. COOPER, OLIN A. Fos'rnni c0 to simultaneously control the said ports, a f 

